<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
        function fun1() {
            alert("页面加载事件");
        }
        function fun2() {
            alert("点击span");
        }
        function fun3() {
            alert("离焦事件");
        }
        function fun4() {
            alert("光标移入事件");
        }
        function fun5() {
            alert("下拉菜单变化");
        }
    </script>
</head>
        <body ><!--onload="fun1()"-->
            <span onclick="fun2();">aaa</span><br/>
            <button  id="bt">按钮</button><br/>
            onblur<input type="text" onblur="fun3();"><br/>
            focus<input type="text" onfocus="fun3();"><br/>
            <select onchange="fun5()">
                <option>1</option>
                <option>2</option>
                <option>3</option>
                <option>4</option>
            </select>
        </body>
</html>